5-(3,5-Di­fluoro­phen­yl)-1-(4-fluoro­phen­yl)-3-tri­fluoro­methyl-1H-pyrazole

Manoj Kumar, K.E.; Suchetan, P.A.; Palakshamurthy, B.S.; Madan Kumar, S.; Lokanath, N.K.; Sreenivasa, S.

doi:10.1107/S1600536813032650

organic compounds

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Volume 70| Part 1| January 2014| Page o19

https://doi.org/10.1107/S1600536813032650

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5-(3,5-Difluorophenyl)-1-(4-fluorophenyl)-3-trifluoromethyl-1H-pyrazole

Karikere Ekanna Manoj Kumar,^a Parameshwar Adimoole Suchetan,^a Bandrehalli Siddagangaiah Palakshamurthy,^b Shankar Madan Kumar,^c Neratur Krishnappagowda Lokanath ^c and Swamy Sreenivasa ^a ^*

^aDepartment of Studies and Research in Chemistry, U.C.S., Tumkur University, Tumkur, Karnataka 572 103, India, ^bDepartment of Studies and Research in Physics, U.C.S., Tumkur University, Tumkur, Karnataka 572 103, India, and ^cDepartment of Studies in Physics, University of Mysore, Manasagangotri, Mysore, India
^*Correspondence e-mail: drsreenivasa@yahoo.co.in

(Received 25 November 2013; accepted 1 December 2013; online 7 December 2013)

In the title compound, C₁₆H₈F₆N₂, the dihedral angle between the pyrazole and difluorobenzene rings is 50.30 (13)°, while those between the pyrazole and fluorobenzene rings and between the difluorobenzene and fluorobenzene rings are 38.56 (13) and 53.50 (11)°, respectively. Aromatic π–π stacking interactions between adjacent difluorobenzene rings [centroid–centroid separation = 3.6082 (11) Å] link the molecules into dimers parallel to [21-2].

CCDC reference: 974623

Related literature

For background to pyrazole derivatives and their uses, see: Ramaiah et al. (1999 ). For a similar structure, see: Sreenivasa et al. (2013 ).

Experimental

Crystal data

C₁₆H₈F₆N₂
M_r = 342.24
Triclinic, $[P \overline 1]$
a = 7.2535 (3) Å
b = 8.6686 (4) Å
c = 11.7690 (5) Å
α = 70.909 (1)°
β = 80.139 (1)°
γ = 88.077 (1)°
V = 688.78 (5) Å³
Z = 2
Cu Kα radiation
μ = 1.39 mm⁻¹
T = 293 K
0.39 × 0.35 × 0.29 mm

Data collection

Bruker APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2009 ) T_min = 0.611, T_max = 0.669
7069 measured reflections
2181 independent reflections
2040 reflections with I > 2σ(I)
R_int = 0.042

Refinement

R[F² > 2σ(F²)] = 0.054
wR(F²) = 0.181
S = 1.11
2181 reflections
217 parameters
H-atom parameters constrained
Δρ_max = 0.45 e Å⁻³
Δρ_min = −0.48 e Å⁻³

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT-Plus (Bruker, 2009); data reduction: SAINT-Plus; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: Mercury (Macrae et al., 2008 ); software used to prepare material for publication: SHELXL97.

Supporting information

CCDC reference: 974623

Crystal structure: contains datablocks I, New_Global_Publ_Block. DOI: https://doi.org/10.1107/S1600536813032650/wm2788sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536813032650/wm2788Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S1600536813032650/wm2788Isup3.cml

checkCIF report

Comment top

The pyrazole entity is an important moiety in numerous natural and synthetic compounds and in medicinal chemistry (see, for example: Ramaiah et al., 1999). As part of our studies in this area, the title compound, C₁₆H₈F₆N₂, was synthesized and its crystal structure determined.

In the title compound, the dihedral angle between the pyrazole and the difluorobenzene rings is 50.30 (13)°, while those between the pyrazole and the fluorobenzene rings and the difluorobenzene and the fluorobenzene rings are, respectively, 38.56 (13)° and 53.50 (11)°. Compared to these values, the dihedral angles between the pyrazole-benzoic acid ring, pyrazole-fluorobenzene ring and fluorobenzene-benzoic acid ring in the structure of the related compound 2-[5-(2-fluorophenyl)-3-isobutyl-1H-pyrazol-1-yl]benzoic acid (Sreenivasa et al., 2013) are 53.1 (1)°, 52.1 (1)° and 62.1 (1)°, respectively. Aromatic π–π stacking interactions between the difluorobenzene rings in the title structure [centroid-to-centroid separation = 3.6082 (11) Å] links the molecules parallel to [212] in the crystal structure (Fig 2).

Related literature top

For background to pyrazole derivatives and their uses, see: Ramaiah et al. (1999). For a similar structure, see: Sreenivasa et al. (2013).

Experimental top

1-(3,5-Difluorophenyl)-4,4,4-trifluorobutane-1,3-dione (0.015 mmol) and (4-fluorophenyl)hydrazine (0.015 mmol) were taken in dry ethanol (14 ml) and the reaction mixture was stirred for 6 h at 348 K under a nitrogen atmosphere. The reaction was monitored by TLC and the excess solvent was removed by vacuum to obtain the crude compound. It was purified by column chromatography using dichloromethane and ethanol (9:1) as eluent.

Yellow prisms suitable for diffraction studies were grown by slow evaporation of the solvent system: dichloromethane and methanol (9:1).

Structure description top

For background to pyrazole derivatives and their uses, see: Ramaiah et al. (1999). For a similar structure, see: Sreenivasa et al. (2013).

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT-Plus (Bruker, 2009); data reduction: SAINT-Plus (Bruker, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: Mercury (Macrae et al., 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top

	Fig. 1. The molecular structure of the title compound, showing the atom-labeling scheme. Displacement ellipsoids are drawn at the 50% probability level.
	Fig. 2. Aromatic Cg···Cg stacking interactions observed in the crystal structure of the title compound. [Cg is the centroid of the difluorobenzene ring. H-atoms are omitted for clarity.]

5-(3,5-Difluorophenyl)-1-(4-fluorophenyl)-3-trifluoromethyl-1H-pyrazole top

Crystal data top

C₁₆H₈F₆N₂	F(000) = 344
M_r = 342.24	Prism
Triclinic, P1	D_x = 1.650 Mg m⁻³
Hall symbol: -P 1	Melting point: 456 K
a = 7.2535 (3) Å	Cu Kα radiation, λ = 1.54178 Å
b = 8.6686 (4) Å	Cell parameters from 1234 reflections
c = 11.7690 (5) Å	θ = 4.0–64.8°
α = 70.909 (1)°	µ = 1.39 mm⁻¹
β = 80.139 (1)°	T = 293 K
γ = 88.077 (1)°	Prism, yellow
V = 688.78 (5) Å³	0.39 × 0.35 × 0.29 mm
Z = 2

Data collection top

Bruker APEXII CCD diffractometer	2181 independent reflections
Radiation source: fine-focus sealed tube	2040 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.042
φ and ω scans	θ_max = 64.8°, θ_min = 4.0°
Absorption correction: multi-scan (SADABS; Bruker, 2009)	h = −8→8
T_min = 0.611, T_max = 0.669	k = −9→10
7069 measured reflections	l = −13→13

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.054	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.181	H-atom parameters constrained
S = 1.11	w = 1/[σ²(F_o²) + (0.1212P)² + 0.5142P] where P = (F_o² + 2F_c²)/3
2181 reflections	(Δ/σ)_max < 0.001
217 parameters	Δρ_max = 0.45 e Å⁻³
0 restraints	Δρ_min = −0.48 e Å⁻³

Crystal data top

C₁₆H₈F₆N₂	γ = 88.077 (1)°
M_r = 342.24	V = 688.78 (5) Å³
Triclinic, P1	Z = 2
a = 7.2535 (3) Å	Cu Kα radiation
b = 8.6686 (4) Å	µ = 1.39 mm⁻¹
c = 11.7690 (5) Å	T = 293 K
α = 70.909 (1)°	0.39 × 0.35 × 0.29 mm
β = 80.139 (1)°

Data collection top

Bruker APEXII CCD diffractometer	2181 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2009)	2040 reflections with I > 2σ(I)
T_min = 0.611, T_max = 0.669	R_int = 0.042
7069 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.054	0 restraints
wR(F²) = 0.181	H-atom parameters constrained
S = 1.11	Δρ_max = 0.45 e Å⁻³
2181 reflections	Δρ_min = −0.48 e Å⁻³
217 parameters

Special details top

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'s involving l.s. planes.

Refinement. Refinement of F² against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The threshold expression of F² > 2σ(F²) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F² are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
F5	0.4695 (2)	0.16122 (18)	0.61518 (14)	0.0259 (4)
F4	0.0082 (2)	0.5540 (2)	0.60896 (14)	0.0277 (4)
F3	0.8754 (2)	1.09529 (19)	0.57955 (14)	0.0311 (4)
F2	0.8448 (2)	1.0637 (2)	0.77056 (15)	0.0338 (5)
F6	0.7353 (3)	−0.0365 (2)	1.12881 (15)	0.0368 (5)
F1	1.0813 (2)	0.9640 (2)	0.68380 (16)	0.0329 (5)
N2	0.7064 (3)	0.5860 (3)	0.80633 (18)	0.0181 (5)
C8	0.7111 (3)	0.4265 (3)	0.8934 (2)	0.0178 (6)
C2	0.5326 (3)	0.3904 (3)	0.6683 (2)	0.0186 (6)
H2	0.6510	0.3520	0.6815	0.022*
C10	0.5548 (4)	0.1787 (3)	1.0287 (2)	0.0231 (6)
H10	0.4464	0.1152	1.0651	0.028*
C7	0.6008 (3)	0.6408 (3)	0.7159 (2)	0.0178 (5)
C3	0.4110 (4)	0.3037 (3)	0.6324 (2)	0.0188 (5)
C14	0.7893 (3)	0.8337 (3)	0.7149 (2)	0.0191 (6)
C4	0.2343 (3)	0.3540 (3)	0.6116 (2)	0.0196 (6)
H4	0.1552	0.2928	0.5875	0.024*
C5	0.1808 (3)	0.5007 (3)	0.6286 (2)	0.0196 (6)
N1	0.8244 (3)	0.7042 (3)	0.80627 (19)	0.0197 (5)
C16	0.8973 (3)	0.9877 (3)	0.6872 (2)	0.0222 (6)
C11	0.7271 (4)	0.1186 (3)	1.0535 (2)	0.0252 (6)
C6	0.2943 (3)	0.5943 (3)	0.6650 (2)	0.0191 (6)
H6	0.2529	0.6918	0.6763	0.023*
C1	0.4720 (3)	0.5386 (3)	0.6844 (2)	0.0174 (5)
C13	0.8827 (4)	0.3653 (3)	0.9218 (2)	0.0230 (6)
H13	0.9914	0.4288	0.8860	0.028*
C15	0.6500 (3)	0.8044 (3)	0.6551 (2)	0.0187 (6)
H15	0.6018	0.8771	0.5902	0.022*
C9	0.5463 (3)	0.3358 (3)	0.9483 (2)	0.0207 (6)
H9	0.4315	0.3799	0.9314	0.025*
C12	0.8922 (4)	0.2094 (4)	1.0036 (2)	0.0276 (6)
H12	1.0060	0.1672	1.0243	0.033*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
F5	0.0287 (8)	0.0245 (8)	0.0340 (9)	0.0044 (6)	−0.0110 (6)	−0.0196 (7)
F4	0.0148 (7)	0.0429 (10)	0.0349 (9)	0.0067 (6)	−0.0103 (6)	−0.0230 (8)
F3	0.0322 (9)	0.0291 (9)	0.0316 (9)	−0.0068 (7)	−0.0084 (7)	−0.0073 (7)
F2	0.0414 (10)	0.0309 (9)	0.0371 (10)	−0.0063 (7)	−0.0009 (7)	−0.0241 (8)
F6	0.0465 (10)	0.0285 (10)	0.0311 (9)	−0.0012 (8)	−0.0096 (8)	−0.0021 (7)
F1	0.0195 (8)	0.0299 (9)	0.0533 (11)	−0.0036 (6)	−0.0088 (7)	−0.0169 (8)
N2	0.0154 (10)	0.0240 (12)	0.0198 (11)	−0.0024 (8)	−0.0037 (8)	−0.0131 (9)
C8	0.0225 (12)	0.0211 (13)	0.0150 (11)	−0.0015 (10)	−0.0050 (9)	−0.0116 (10)
C2	0.0149 (11)	0.0263 (14)	0.0191 (12)	0.0019 (10)	−0.0053 (9)	−0.0125 (10)
C10	0.0284 (13)	0.0241 (14)	0.0184 (13)	−0.0058 (10)	0.0013 (10)	−0.0113 (11)
C7	0.0135 (11)	0.0257 (13)	0.0197 (12)	0.0001 (9)	−0.0044 (9)	−0.0140 (10)
C3	0.0215 (12)	0.0192 (12)	0.0195 (12)	0.0013 (9)	−0.0033 (9)	−0.0116 (10)
C14	0.0180 (12)	0.0240 (13)	0.0197 (12)	−0.0010 (10)	−0.0027 (9)	−0.0135 (11)
C4	0.0178 (12)	0.0267 (14)	0.0180 (12)	−0.0040 (10)	−0.0036 (9)	−0.0114 (10)
C5	0.0115 (11)	0.0315 (14)	0.0173 (12)	0.0010 (10)	−0.0032 (9)	−0.0098 (10)
N1	0.0175 (10)	0.0232 (12)	0.0227 (11)	−0.0031 (8)	−0.0043 (8)	−0.0127 (9)
C16	0.0202 (12)	0.0267 (14)	0.0246 (14)	0.0011 (10)	−0.0054 (10)	−0.0140 (11)
C11	0.0373 (16)	0.0224 (14)	0.0167 (12)	0.0003 (11)	−0.0061 (11)	−0.0067 (10)
C6	0.0182 (12)	0.0235 (13)	0.0194 (12)	0.0025 (10)	−0.0047 (9)	−0.0116 (10)
C1	0.0157 (11)	0.0241 (13)	0.0159 (12)	−0.0018 (9)	−0.0030 (9)	−0.0108 (10)
C13	0.0214 (13)	0.0283 (14)	0.0219 (13)	−0.0032 (10)	−0.0057 (10)	−0.0103 (11)
C15	0.0182 (12)	0.0215 (13)	0.0208 (12)	0.0022 (10)	−0.0059 (9)	−0.0116 (10)
C9	0.0180 (12)	0.0303 (14)	0.0192 (12)	0.0001 (10)	−0.0018 (9)	−0.0157 (11)
C12	0.0278 (14)	0.0321 (15)	0.0258 (14)	0.0027 (11)	−0.0109 (11)	−0.0105 (12)

Geometric parameters (Å, º) top

F5—C3	1.359 (3)	C7—C15	1.390 (4)
F4—C5	1.351 (3)	C7—C1	1.478 (3)
F3—C16	1.336 (3)	C3—C4	1.376 (4)
F2—C16	1.349 (3)	C14—N1	1.329 (3)
F6—C11	1.353 (3)	C14—C15	1.399 (3)
F1—C16	1.339 (3)	C14—C16	1.483 (3)
N2—N1	1.357 (3)	C4—C5	1.383 (4)
N2—C7	1.367 (3)	C4—H4	0.9300
N2—C8	1.430 (3)	C5—C6	1.383 (3)
C8—C13	1.388 (4)	C11—C12	1.385 (4)
C8—C9	1.390 (4)	C6—C1	1.390 (3)
C2—C3	1.378 (3)	C6—H6	0.9300
C2—C1	1.404 (4)	C13—C12	1.387 (4)
C2—H2	0.9300	C13—H13	0.9300
C10—C11	1.378 (4)	C15—H15	0.9300
C10—C9	1.387 (4)	C9—H9	0.9300
C10—H10	0.9300	C12—H12	0.9300

N1—N2—C7	112.0 (2)	F3—C16—F1	107.1 (2)
N1—N2—C8	118.73 (19)	F3—C16—F2	106.1 (2)
C7—N2—C8	129.3 (2)	F1—C16—F2	106.02 (19)
C13—C8—C9	121.0 (2)	F3—C16—C14	111.8 (2)
C13—C8—N2	118.7 (2)	F1—C16—C14	112.6 (2)
C9—C8—N2	120.3 (2)	F2—C16—C14	112.7 (2)
C3—C2—C1	117.9 (2)	F6—C11—C10	118.5 (2)
C3—C2—H2	121.1	F6—C11—C12	118.7 (2)
C1—C2—H2	121.1	C10—C11—C12	122.8 (3)
C11—C10—C9	118.7 (2)	C5—C6—C1	118.2 (2)
C11—C10—H10	120.6	C5—C6—H6	120.9
C9—C10—H10	120.6	C1—C6—H6	120.9
N2—C7—C15	106.9 (2)	C6—C1—C2	120.5 (2)
N2—C7—C1	125.3 (2)	C6—C1—C7	119.4 (2)
C15—C7—C1	127.6 (2)	C2—C1—C7	120.0 (2)
F5—C3—C4	118.0 (2)	C12—C13—C8	120.0 (2)
F5—C3—C2	118.2 (2)	C12—C13—H13	120.0
C4—C3—C2	123.8 (2)	C8—C13—H13	120.0
N1—C14—C15	113.4 (2)	C7—C15—C14	103.6 (2)
N1—C14—C16	118.8 (2)	C7—C15—H15	128.2
C15—C14—C16	127.8 (2)	C14—C15—H15	128.2
C3—C4—C5	116.2 (2)	C10—C9—C8	119.3 (2)
C3—C4—H4	121.9	C10—C9—H9	120.3
C5—C4—H4	121.9	C8—C9—H9	120.3
F4—C5—C4	117.9 (2)	C11—C12—C13	118.0 (2)
F4—C5—C6	118.7 (2)	C11—C12—H12	121.0
C4—C5—C6	123.4 (2)	C13—C12—H12	121.0
C14—N1—N2	104.07 (19)

N1—N2—C8—C13	−37.8 (3)	C9—C10—C11—F6	−177.9 (2)
C7—N2—C8—C13	139.9 (2)	C9—C10—C11—C12	1.4 (4)
N1—N2—C8—C9	142.0 (2)	F4—C5—C6—C1	−179.7 (2)
C7—N2—C8—C9	−40.3 (3)	C4—C5—C6—C1	0.7 (4)
N1—N2—C7—C15	−1.2 (3)	C5—C6—C1—C2	−0.6 (4)
C8—N2—C7—C15	−179.0 (2)	C5—C6—C1—C7	176.2 (2)
N1—N2—C7—C1	174.1 (2)	C3—C2—C1—C6	0.3 (4)
C8—N2—C7—C1	−3.7 (4)	C3—C2—C1—C7	−176.5 (2)
C1—C2—C3—F5	179.2 (2)	N2—C7—C1—C6	134.5 (2)
C1—C2—C3—C4	0.0 (4)	C15—C7—C1—C6	−51.2 (3)
F5—C3—C4—C5	−179.2 (2)	N2—C7—C1—C2	−48.6 (3)
C2—C3—C4—C5	0.0 (4)	C15—C7—C1—C2	125.7 (3)
C3—C4—C5—F4	180.0 (2)	C9—C8—C13—C12	1.8 (4)
C3—C4—C5—C6	−0.4 (4)	N2—C8—C13—C12	−178.4 (2)
C15—C14—N1—N2	0.5 (3)	N2—C7—C15—C14	1.4 (2)
C16—C14—N1—N2	−179.3 (2)	C1—C7—C15—C14	−173.8 (2)
C7—N2—N1—C14	0.5 (2)	N1—C14—C15—C7	−1.2 (3)
C8—N2—N1—C14	178.55 (19)	C16—C14—C15—C7	178.5 (2)
N1—C14—C16—F3	167.2 (2)	C11—C10—C9—C8	1.3 (3)
C15—C14—C16—F3	−12.5 (3)	C13—C8—C9—C10	−2.9 (3)
N1—C14—C16—F1	46.5 (3)	N2—C8—C9—C10	177.3 (2)
C15—C14—C16—F1	−133.1 (3)	F6—C11—C12—C13	176.8 (2)
N1—C14—C16—F2	−73.3 (3)	C10—C11—C12—C13	−2.4 (4)
C15—C14—C16—F2	107.0 (3)	C8—C13—C12—C11	0.8 (4)

Experimental details

Crystal data
Chemical formula	C₁₆H₈F₆N₂
M_r	342.24
Crystal system, space group	Triclinic, P1
Temperature (K)	293
a, b, c (Å)	7.2535 (3), 8.6686 (4), 11.7690 (5)
α, β, γ (°)	70.909 (1), 80.139 (1), 88.077 (1)
V (Å³)	688.78 (5)
Z	2
Radiation type	Cu Kα
µ (mm⁻¹)	1.39
Crystal size (mm)	0.39 × 0.35 × 0.29

Data collection
Diffractometer	Bruker APEXII CCD
Absorption correction	Multi-scan (SADABS; Bruker, 2009)
T_min, T_max	0.611, 0.669
No. of measured, independent and observed [I > 2σ(I)] reflections	7069, 2181, 2040
R_int	0.042
(sin θ/λ)_max (Å⁻¹)	0.587

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.054, 0.181, 1.11
No. of reflections	2181
No. of parameters	217
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.45, −0.48

Computer programs: APEX2 (Bruker, 2009), SAINT-Plus (Bruker, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), Mercury (Macrae et al., 2008).

Acknowledgements

The authors acknowledge the IOE X-ray diffractometer Facility, University of Mysore, Mysore, for the data collection.

References

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